Globally optimal,minimum stored energy,double‐doughnut superconducting magnets

The use of the minimum stored energy current density map–based methodology of designing closed‐bore symmetric superconducting magnets was described recently. The technique is further developed to cater for the design of interventional‐type MRI systems, and in particular open symmetric magnets of the double‐doughnut configuration. This extends the work to multiple magnet domain configurations. The use of double‐doughnut magnets in MRI scanners has previously been hindered by the ability to deliver strong magnetic fields over a sufficiently large volume appropriate for imaging, essentially limiting spatial resolution, signal‐to‐noise ratio, and field of view. The requirement of dedicated interventional space restricts the manner in which the coils can be arranged and placed. The minimum stored energy optimal coil arrangement ensures that the field strength is maximized over a specific region of imaging. The design method yields open, dual‐domain magnets capable of delivering greater field strengths than those used prior to this work, and at the same time it provides an increase in the field‐of‐view volume. Simulation results are provided for 1‐T double‐doughnut magnets with at least a 50‐cm 1‐ppm (parts per million) field of view and 0.7‐m gap between the two doughnuts. Magn Reson Med, 2010. © 2009 Wiley‐Liss, Inc.     

In utero exposure to steroid contraceptives and survival during infancy.

A cohort study was conducted in Chiang Mai, northern Thailand, in 1,431 children of women who had used the injectable contraceptive Depo-Provera (The Upjohn Company, Kalamazoo, Michigan), 565 children of women who had used oral contraceptives during pregnancy, and a group of 2,307 control infants with no hormonal contraceptive exposures. In follow-up interviews, information was obtained on stillbirths and deaths. Cause of death was ascertained by interview, death certificate, or medical record, and underlying causes of death were ascribed by a panel. The children exposed in utero to Depo-Provera had higher neonatal and infant mortality rates (44.3 and 62.9 per 1,000 live births, respectively) than did the controls (19.8 and 29.1 per 1,000 live births). Mortality in infants exposed in utero to oral contraceptives was intermediate between that in the other two groups. Adjustment by logistic regression showed no significantly increased risk of mortality among infants exposed to oral contraceptives, but the odds ratio for death was significantly increased with Depo-Provera exposures due to accidental pregnancy (odds ratio (OR) = 1.8 (95% confidence interval (Cl) 1.1-3.0) for neonatal deaths; OR = 2.0 (95% Cl 1.3-3.2) for infant deaths). Adjustment for low birth weight reduced the risks, suggesting that low birth weight may act as an intermediate determinant of Depo-Provera-associated mortality. Among the accidental pregnancies with Depo-Provera, there was a relation between shorter injection-to-conception intervals, when maternal blood levels of the drug are high, and an increased risk of mortality. The odds ratios for neonatal mortality were 2.5 (95% Cl 1.1-5.7), 2.1 (95% Cl 1.0-4.6), and 0.9 (95% Cl 0.4-2.4) for injection-to-conception intervals of less than or equal to 4, 5-8, and greater than 9 weeks, respectively. Adjustment for low birth weight reduced these risks. Chi-square tests for trend were highly significant. Similar associations were also observed between Depo-Provera accidental pregnancies and risks of low birth weight. Thus, infants from accidental pregnancies that occur 1-2 months after a 150-mg Depo-Provera injection may be at increased risk for low birth weight and death. However, the attributable risk is low, because such pregnancies are uncommon.     

Effects of Medications on Post-Endoscopic Retrograde Cholangiopancreatography Pancreatitis

Background and Aims: Drug-induced pancreatitis accounts for about 2% of acute pancreatitis. The aim of this study is to determine whether propofol and other medications are associated with increased risk for post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis. Methods: A retrospective study was conducted at a single tertiary care hospital. All patients who underwent ERCP from 2001 to 2004 were included. Diagnosis of acute post-ERCP pancreatitis was based on a consensus definition. Results: A total of 506 patients underwent ERCP. The total incidence of post-ERCP pancreatitis was 7.1%. There was no significant difference in post-ERCP pancreatitis between patients who received propofol compared to patients who received midazolam and fentanyl (9.0 vs. 5.9%, p = 0.18). Patients receiving an angiotensin receptor blocker were approximately 4 times more likely to develop post-ERCP pancreatitis (OR = 4.1, 95% CI 1.6–10.9). Patients younger than 65 years and smokers also had higher risk of developing acute post-ERCP pancreatitis than those who were older than 65 years (OR = 3.9, 95% CI 1.7–9.1) and non-smokers (OR = 2.8, 95% CI 1.3–6.2). Conclusions: Propofol is a safe sedative drug for ERCP without additional risk of developing acute post-ERCP pancreatitis. Use of angiotensin receptor blockers, smoking and younger age are independent risk factors for post-ERCP pancreatitis.     

The long-term growth and development of children exposed to Depo-Provera during pregnancy or lactation.

Children exposed to the injectable contraceptive Depo-Provera (DMPA) during pregnancy (N = 1,207), and/or during breastfeeding (N = 1,215) were exposures during pregnancy or breastfeeding. Weights and heights were measured for all children, and information on signs of puberty obtained for children aged ten and over. Cross-sectional weights and heights by age of DMPA-exposed children were similar to those for controls. Children with DMPA exposure during pregnancy and lactation had an increased risk of suboptimal growth in height, defined as less than two Z scores on NCHS standards (RR = 1.4, 95% CI 1.2-1.8). However, after adjustment for socioeconomic factors by multiple logistic regression, there was no increased risk of impaired growth among the DMPA-exposed children (RR = 1.1, 95% CI 0.8 - 1.6). With the exception of a delay in onset of reported pubic hair growth among DMPA-exposed girls, there were no significant effects on attainment of puberty. We conclude that use of DMPA during pregnancy or breastfeeding does not adversely affect the long-term growth and development of children.     

Childhood‐onset schizophrenia/autistic disorder and t(1;7) reciprocal translocation: Identification of a BAC contig spanning the translocation breakpoint at 7q21

Childhood‐onset schizophrenia (COS) is defined by the development of first psychotic symptoms by age 12. While recruiting patients with COS refractory to conventional treatments for a trial of atypical antipsychotic drugs, we discovered a unique case who has a familial t(1;7)(p22;q21) reciprocal translocation and onset of psychosis at age 9. The patient also has symptoms of autistic disorder, which are usually transient before the first psychotic episode among 40–50% of the childhood schizophrenics but has persisted in him even after the remission of psychosis. Cosegregating with the translocation, among the carriers in the family available for the study, are other significant psychopathologies, including alcohol/drug abuse, severe impulsivity, and paranoid personality and language delay. This case may provide a model for understanding the genetic basis of schizophrenia or autism. Here we report the progress toward characterization of genomic organization across the translocation breakpoint at 7q21. The polymorphic markers, D7S630/D7S492 and D7S2410/D7S646, immediately flanking the breakpoint, may be useful for further confirming the genetic linkage for schizophrenia or autism in this region. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:749–753, 2000. Published 2000 Wiley‐Liss, Inc.     

Naturally processed peptides from HLA-DQ7 (α1*0501-β1*0301): influence of both α and β chain polymorphism in the HLA-DQ peptide binding specificity

Self peptides bound to HLA-DQ7 (α1*0501-β1*0301), one of the HLA molecules associated with protection against insulin-dependent diabetes mellitus, were characterized after their acid elution from immunoaffinity-purified HLA-DQ7 (α1*0501-β1*0301) molecules. The majority of these self peptides derived from membrane-associated proteins including HLA class I, class II, class II-associated invariant chain peptide and the transferrin-receptor (TfR). By in vitro binding assays, the specificity of these endogenous peptides for HLA-DQ7 (α1*0501-β1*0301) molecules was confirmed. Among these peptides, the binding specificity of the TfR 215 – 230 self peptide was further examined on a variety of HLA-DQ and DR dimers. Several findings emerged from this analysis: (1) this peptide displayed HLA-DQ allelic specificity, binding only to HLA-DQ7 (α1*0501-β1*0301); (2) when either the DQα or DQβ chain was exchanged, little or no binding was observed, indicating that specificity of HLA-DQ peptide binding was determined by polymorphic residues of both the α and β chains. (3) Unexpectedly, the TfR 215 – 230 self peptide, eluted from DQ, was promiscuous with regard to HLA-DR binding. This distinct DR and DQ binding pattern could reflect the structure of these two molecules as recently evidenced by crystallography.     

Two-year clinical outcomes following lower limb endovascular revascularisation for chronic limb-threatening ischaemia at a tertiary Asian vascular centre in Singapore

INTRODUCTIONPercutaneous transluminal angioplasty (PTA) is commonly used to treat patients with chronic limb-threatening ischaemia (CLTI). This study aimed to examine the mortality and functional outcomes of patients with CLTI who predominantly had diabetes mellitus in a multi-ethnic Asian population in Singapore.METHODSPatients with CLTI who underwent PTA between January 2015 and March 2017 at the Vascular Unit at Singapore General Hospital, Singapore, were studied. Primary outcome measures were 30-day unplanned readmission, two-year major lower extremity amputation (LEA), mortality rates, and ambulation status at one, six and 12 months.RESULTSA total of 221 procedures were performed on 207 patients, of whom 184 (88.9%) were diabetics. The one-, six- and 12-month mortality rate was 7.7%, 16.4% and 21.7%, respectively. The two-year LEA rate was 30.0%. At six and 12 months, only 96 (46.4%) and 93 (44.9%) patients were ambulant, respectively. Multivariate analysis revealed that preoperative ambulatory status, haemoglobin, Wound Ischaemia and foot Infection (WIfI) score, and end-stage renal failure (ESRF) were independent predictors of one-year ambulatory status. Predictors of mortality at one, six and 12 months were ESRF, preoperative albumin level, impaired functional status and employment status.CONCLUSIONPTA for CLTI was associated with low one-year mortality and two-year LEA rates but did not significantly improve ambulation status. ESRF and hypoalbuminaemia were independent predictors of mortality. ESRF/CKD and WIfI score were independent predictors of loss of ambulation at six months and one year. We need better risk stratification for patients with CLTI to decide between initial revascularisation and an immediate LEA policy.